Heat exchanger distributor swirl vane

ABSTRACT

A vapor cycle heat exchanger has a plurality of heat exchanger lines and a distributor. The distributor comprises a distributor housing, a swirl vane, an atomizing nozzle, a plurality of nozzles, and a fluid line intersection. The distributor housing defines a main distributor line configured to receive a non-homogenous flow of the two-phase refrigerant fluid. The swirl vane is disposed within the main distributor line and configured to distribute the non-homogeneous flow into a symmetric fluid distribution. The atomizing nozzle is disposed downstream of the swirl vane. The routing lines each lead to one of the plurality of heat exchanger lines. The main distributor line branches into the routing lines at the fluid line intersection, which is situated downstream of the nozzle.

BACKGROUND

The present invention relates generally to heat exchangers, and moreparticularly to a swirl vane for a heat exchanger distributor.

Heat exchangers are used in a variety of applications to transfer andtransport heat, and often include a plurality of separate fluid linesthrough fins or planes that increase surface area for thermal transfer.Heat exchangers commonly use distributors to evenly distribute coolantfrom a single inlet line across these separate heat exchanger lines. Toensure efficient heat transfer, distributors must distribute fluidvolume from inlet lines substantially evenly across heat exchangerlines.

Vapor cycle heat exchangers are often used to cool electronics and othercomponents with high thermal loads. As used in the present application,the term “vapor cycle heat exchanger” is defined as a closed system heatexchanger that transfers heat via cyclical phase changes of flowingrefrigerant fluid. Many stages of vapor cycle heat exchangers carryrefrigerant in non-homogeneous state mixtures of liquid and gas.

It is desired to ensure efficient heat transfer distributors in vaporcycle heat exchangers by providing equal refrigerant mass down each heatexchanger line, and substantially the same proportion of liquid to gasdown each heat exchanger line.

SUMMARY

The present invention is directed toward a vapor cycle heat exchangerwith a plurality of heat exchanger lines and a distributor. Thedistributor comprises a distributor housing, a swirl vane, an atomizingnozzle, a plurality of nozzles, and a fluid line intersection. Thedistributor housing defines a main distributor line configured toreceive a non-homogenous flow of the two-phase coolant fluid. The swirlvane is disposed within the main distributor line and configured todistribute the non-homogeneous flow into a symmetric fluid distribution.The atomizing nozzle is disposed downstream of the swirl vane. Therouting lines each lead to one of the plurality of heat exchanger lines.The main distributor line branches into the routing lines at the fluidline intersection, which is situated downstream of the nozzle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a simplified cross-sectional view of a heat exchanger system.

FIG. 2 is a perspective view of a distributor of the heat exchangersystem of FIG. 1.

FIG. 3a is a perspective view of a swirl vane in the distributor of FIG.2.

FIG. 3b is a cross-sectional view of the swirl vane of FIG. 3 a.

FIG. 4 is a schematic view of the distributor of FIG. 2

While the above-identified figures set forth one or more embodiments ofthe present disclosure, other embodiments are also contemplated, asnoted in the discussion. In all cases, this disclosure presents theinvention by way of representation and not limitation. It should beunderstood that numerous other modifications and embodiments can bedevised by those skilled in the art, which fall within the scope andspirit of the principles of the invention. The figures may not be drawnto scale, and applications and embodiments of the present invention mayinclude features and components not specifically shown in the drawings.

DETAILED DESCRIPTION

The present invention concerns a swirl vane disposed in a maindistributor line of a distributor for a vapor cycle heat exchanger witha plurality of heat exchanger lines. The swirl vane distributesnon-homogeneous mixtures of gas and liquid refrigerant into arotationally symmetric fluid distribution. A nozzle is locateddownstream of the swirl vane. The swirl vane ensures that liquidrefrigerant entering the nozzle is substantially evenly distributedacross a plurality of routing lines, and that the proportion of liquidto gas in each routine line is substantially the same.

FIG. 1 is a simplified cross-sectional view of heat exchanger system 10,comprising expansion valve 12, refrigerant inlet 14, expansion chamber16, distributor inlet 18, distributor 20 (with distributor housing 22,main distributor line 24, swirl vane assembly 26, nozzle 28, fluidintersection 30, routing lines 32, and branch sections 34), and heatexchanger 36 (with heat exchanger lines 38, heat exchanger inlets 40).

Heat exchanger system 10 is portion of a vapor cycle heat exchanger.Heat exchanger 10 can, for example, carry refrigerants fluids such asFreon, CO₂, R134 refrigerants, or other refrigerants. Heat exchangersystem 10 can be used in a wide variety of applications, including butnot limited to air and electronics cooling. Expansion valve 12 receivesliquid or mostly-liquid refrigerant via refrigerant inlet 14.Refrigerant is allowed to expand and evaporate in expansion chamber 16,producing a mixture of liquid and gas that distributor inlet 18 carriesto distributor 20. Distributor 20 distributes refrigerant substantiallyuniformly between a multitude of heat exchanger lines 38 of heatexchanger 36. Each heat exchanger line 38 receives refrigerant fromdistributor 20 at a corresponding heat exchanger inlet 40.

Distributor 20 includes distributor housing 22, a rigid structure thatextends axially along distributor axis A and forms the structure ofdistributor 20. Distributor housing 20 can, in some embodiments, be arigid metal structure formed, for example, of cast aluminum. In otherembodiments, distributor housing 20 can be an injection molded polymerstructure. Distributor housing 20 defines main distributor line 24, asubstantially axial fluid flow path that carries refrigerant fluid flowF_(c). Refrigerant fluid flow F_(c) contains a mixture of liquid and gasrefrigerant, and is initially non-homogeneously distributed within maindistributor line 24. The particular proportions of refrigerant fluid inliquid and gas states can vary based on application and refrigerantfluid selection. The initial non-homogeneous distribution of refrigerantfluid flow F_(c) can, for example, take the form of heavier liquidrefrigerant pooling along a bottom portion of main distributor line 24,while coolant gas is correspondingly forced upwards. Swirl vane assembly26, a flow directing member within main distributor line 24,redistributes the non-homogeneous fluid of refrigerant fluid flow F_(c)into a substantially symmetric distribution. In at least someembodiments, swirl vane assembly 26 is a rotationally symmetric fan-,helix-, or propeller-shaped guide vane that redistributes refrigerantfluid flow F_(c) into a rotationally symmetric distribution, asdescribed with respect to FIGS. 3a and 3b . Distributions of refrigerantfluid flow F_(c) are discussed in greater detail below with respect toFIG. 4. In some embodiments, swirl vane assembly 26 can be formed as anintegral part of distributor housing 20. In other embodiments, swirlvane assembly 26 can be an insert that is installed within distributorhousing 20, or an overmolded piece about which distributor housing 20 isformed.

Swirl vane assembly 26 preconditions the non-homogeneous mixture ofliquid and gas refrigerant in fluid flow F_(c) to be substantiallysymmetrically distributed about axis A. Downstream of swirl vaneassembly 26, this pre-conditioned refrigerant fluid flow F_(c) passesthrough nozzle 28. Nozzle 28 is a narrow aperture that forms a neck inmain distributor line 24. Refrigerant fluid flow F_(c) passes throughthe constrained aperture of nozzle 28 at high speeds, and is therebyatomized. This atomization of refrigerant flow F_(c) substantiallyhomogenizes liquid and gas distribution immediately downstream of nozzle28, where main distributor line 24 branches at fluid intersection 30into a plurality of routing lines 32. Intersection 30 acts as a flowdivider, separating refrigerant fluid flow F_(c) into a plurality ofsecondary refrigerant flows F_(s), one down each routing line 32. Eachrouting line 32 extends from fluid intersection 30 to a heat exchangerinlet 40 for one of the plurality of heat exchanger lines 38. Furtherdetails of the routing path of routing lines 32 are described below withrespect to FIG. 2. Routing lines 32 include branch sections 34, whichextend axially and radially from fluid intersection 30. Branch sections34 are circumferentially distributed about axis A at fluid intersection30. Refrigerant fluid flow F_(c) is substantially homogeneouslydistributed at fluid intersection 30: the atomized, symmetricaldistribution of refrigerant fluid flow F_(c) at fluid intersection 30ensures that substantially equal refrigerant volumes with substantiallyidentical distributions of liquid and gas refrigerant enter each routingline 32 via corresponding branch sections 34. Consequently, allsecondary refrigerant flows F_(s) have substantially equal volume, andshare substantially the same proportion of liquid to gas as refrigerantfluid flow F_(c). Secondary refrigerant flows F_(s) can subsequentlyseparate (i.e. into liquid and gas layers) downstream of fluidintersection 30, without any impact on the uniformity of fluiddistribution across heat exchanger lines 38, or the overall efficiencyof heat exchanger 36.

FIG. 2 is a perspective view of distributor 20, described above withrespect to FIG. 1. FIG. 2 illustrates distributor housing 22, routinglines 32, branch sections 34, heat exchanger inlets 40, secondarydistribution sections 42, distributor axis A. Distributor housing 20 istransparently to allow routing lines 32 to be seen.

Distributor 20 operates as described above with respect to FIG. 1, withswirl vane assembly 26 and nozzle 28 ensuring substantially uniformrefrigerant distribution across all routing lines 32. Routing lines 32comprise branch sections 34 and secondary distribution sections 42. Inthe depicted embodiment, branch sections 32 are distributedcircumferentially about axis A, and extend axially and radially formfluid intersection 30 to an axially rear-most portion of distributorhousing 22. Secondary distribution sections 42 extend from branchsections 34 to heat exchanger inlets 40. In the depicted embodiment, allheat exchanger inlets 40 are aligned along a heat exchanger line L_(HE).This embodiment corresponds to an arrangement of heat exchanger lines 38(e.g. for each vane or fin of heat exchanger 36) along a single planeintersecting distributor housing 22 at heat exchanger line L_(HE). Inalternative embodiments, heat exchanger inlets 40 can be distributedacross several locations on distributor housing 22, e.g. where heatexchanger 36 comprises multiple planes of heat exchanger lines. In theillustrated embodiment, secondary distribution sections 42 extendaxially and circumferentially from branch sections 34 to heat exchangerinlets 40.

FIGS. 3a and 3b are perspective and cross-sectional views, respectively,of one possible embodiment of swirl vane assembly 26. FIGS. 3a and 3billustrate flow guide vanes 44 and vane connection 46. In the depictedembodiment, swirl vane assembly 26 comprises two flow guide vanes 44joined at vane connection 46, and each swirl vane assembly 26 comprisesa bent half-moon shape. As shown in FIGS. 3a and 3b , flow guide vanes44 are bent sections of substantially uniform thickness, and vaneconnection 46 is a chamfered connection between flow guide vanes 44. Inthis embodiment, parallel surfaces of flow guide vanes 44 are separatedby an axial distance D. Axial distance D is also the spanwise diameterof a circular region R_(C) of each fluid guide vane 44 conforming to acircular shape, and each fluid guide vane 44 comprises two oppositesymmetrically controlled circular and/or oval regions, each covering anangular sweep θ from the center cross-section line. Angular sweep θ can,for example, be 30-60°. More generally, the shape of swirl vane assembly26 is selected such that refrigerant fluid flow F_(c) impinging on swirlvane assembly 26 is constrained by fluid guide vanes 44 and bycylindrical walls of distributor housing 22 to conform to a swirling orvortex pattern. Alternative embodiments of swirl vane assembly 26 can,for example, be helical or propeller-shaped. As described above withrespect to FIG. 1, the vortex imparted on coolant fluid flow F_(c) byswirl vane assembly 26 serves to rearrange the asymmetric distributionof non-homogeneous coolant fluid flow F_(c) upstream of swirl vaneassembly 26 into a rotationally symmetric distribution thatpreconditions refrigerant for increased homogeneity after passingthrough nozzle 28. In some embodiments, swirl vane assembly 26 can becast or molded as a single piece, and/or machined into a desired shape.In other embodiments, swirl vane assembly 26 can be formed from multiplepieces (e.g. as separate flow guide vanes 46) welded or otherwise joinedtogether during manufacturing. The particular geometry of swirl vaneassembly 26 illustrated in FIGS. 3a and 3b comprises only one possibleembodiment, but provides desirable flow characteristics.

FIG. 4 is a schematic view of distributor 20 illustrating thedistribution of refrigerant fluid by swirl vane assembly 26. FIG. 4 alsodepicts distributor housing 22, main distribution line 24, anddistributor axis A. FIG. 4 illustrates the transition of refrigerantfluid flow from a first, asymmetric distribution Dist_(A) to a second,rotationally symmetrical distribution Dist_(S). As shown in FIGS. 1 and4, distributor housing 22 defines a predominantly axial main distributorline 24. Swirl vane assembly 26 is interposed within main distributorline 24, upstream of nozzle 28. Swirl vane assembly 26 imparts arotational component about axis A on fluid velocity within maindistributor line 24, preventing asymmetric pooling of denser liquid orlighter gas in nozzle 28 and fluid intersection 30. Swirl vane assembly26 and nozzle 28 cooperate to ensure that fluid distribution is uniformacross all routing lines 32 branching off of fluid intersection 30. Thisuniformity takes two forms. First, distributor 20 helps ensure thatsubstantially equal volumes of refrigerant fluid reach each routing line32. Second, distributor 20 helps ensure that the proportion of liquid togas is substantially identical in refrigerant reaching each routing line32. This uniformity promotes efficient operation of heat exchanger 36.

Discussion of Possible Embodiments

The following are non-exclusive descriptions of possible embodiments ofthe present invention.

A distributor for a two-phase refrigerant fluid of a vapor cycle heatexchanger having a plurality of heat exchanger lines, the distributorcomprising: a distributor housing defining a main distributor lineconfigured to receive a non-homogenous flow of the two-phase coolantfluid; a swirl vane disposed within the main distributor line andconfigured to distribute the non-homogeneous flow into a symmetric fluiddistribution; an atomizing nozzle disposed downstream of the swirl vane;a plurality of routing lines, each leading to one of the plurality ofheat exchanger lines; and a fluid line intersection situated downstreamof the nozzle, and where the main distributor line branches into theplurality of routing lines.

The distributor of the preceding paragraph can optionally include,additionally and/or alternatively, any one or more of the followingfeatures, configurations and/or additional components:

A further embodiment of the foregoing distributor, wherein the maindistributor line is a cylindrical passage extending along a distributoraxis.

A further embodiment of the foregoing distributor, wherein the symmetricfluid distribution is a substantially rotationally symmetricdistribution of the two-phase fluid about the distributor axis.

A further embodiment of the foregoing distributor, wherein therotationally symmetric distribution comprises a radially outer layer ofliquid, and a radially inner core of gas.

A further embodiment of the foregoing distributor, wherein the routinglines extend axially and radially with respect to the distributor axis,away from the fluid line intersection, and wherein the routing lines areevenly circumferentially distributed about the distributor axis at thefluid line intersection.

A further embodiment of the foregoing distributor, wherein each routingline extends from the fluid line intersection to a line inlet into oneof the plurality of heat exchanger lines, and wherein the line inletsare arranged in a line parallel to the distributor axis.

A further embodiment of the foregoing distributor, wherein the swirlvane is a helical or propeller-shaped vane.

A further embodiment of the foregoing distributor, wherein the swirlvane is an integral part of the distributor housing.

A further embodiment of the foregoing distributor, wherein the swirlvane is a separate component installed within the distributor housing.

A heat exchanger system comprises: a heat exchanger with a plurality ofparallel heat exchanger lines, arranged along a common heat exchangerplane, each heat exchanger line having a line inlet; a distributorhousing defining a main distributor line oriented along a distributoraxis, and configured to receive a non-homogenous flow of the two-phasecoolant fluid; a swirl vane disposed within the main distributor lineand configured to distribute the non-homogeneous flow into arotationally symmetric fluid distribution about the distributor axis; anatomizing nozzle disposed downstream of the swirl vane; a plurality ofrouting lines, each leading to one of the line inlets; and arotationally symmetric fluid line intersection situated downstream ofthe nozzle, and where the main distributor line branches into theplurality of routing lines.

The heat exchanger system of the preceding paragraph can optionallyinclude, additionally and/or alternatively, any one or more of thefollowing features, configurations and/or additional components:

A further embodiment of the foregoing heat exchanger system, wherein theswirl vane is a helical or propeller-shaped vane.

A further embodiment of the foregoing heat exchanger system, wherein theline inlets are arranged in a line formed by the intersection of theheat exchanger plane with the heat exchanger housing.

A further embodiment of the foregoing heat exchanger system, wherein atleast one of the distributor housing and the swirl vane is formed ofaluminum.

SUMMATION

Any relative terms or terms of degree used herein, such as“substantially”, “essentially”, “generally”, “approximately” and thelike, should be interpreted in accordance with and subject to anyapplicable definitions or limits expressly stated herein. In allinstances, any relative terms or terms of degree used herein should beinterpreted to broadly encompass any relevant disclosed embodiments aswell as such ranges or variations as would be understood by a person ofordinary skill in the art in view of the entirety of the presentdisclosure, such as to encompass ordinary manufacturing tolerancevariations, incidental alignment variations, alignment or shapevariations induced by thermal, rotational or vibrational operationalconditions, and the like.

While the invention has been described with reference to an exemplaryembodiment(s), it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the scope of the invention. Inaddition, many modifications may be made to adapt a particular situationor material to the teachings of the invention without departing from theessential scope thereof. Therefore, it is intended that the inventionnot be limited to the particular embodiment(s) disclosed, but that theinvention will include all embodiments falling within the scope of theappended claims.

1. A distributor for a two-phase refrigerant fluid of a vapor cycle heatexchanger having a plurality of heat exchanger lines, the distributorcomprising: a distributor housing defining a main distributor lineconfigured to receive a non-homogenous flow of the two-phase coolantfluid; a swirl vane disposed within the main distributor line andconfigured to distribute the non-homogeneous flow into a symmetric fluiddistribution; an atomizing nozzle disposed downstream of the swirl vane;a plurality of routing lines, each leading to one of the plurality ofheat exchanger lines; and a fluid line intersection situated downstreamof the nozzle, and where the main distributor line branches into theplurality of routing lines.
 2. The distributor of claim 1, wherein themain distributor line is a cylindrical passage extending along adistributor axis.
 3. The distributor of claim 2, wherein the symmetricfluid distribution is a substantially rotationally symmetricdistribution of the two-phase fluid about the distributor axis.
 4. Thedistributor of claim 3, wherein the rotationally symmetric distributioncomprises a radially outer layer of liquid, and a radially inner core ofgas.
 5. The distributor of claim 2, wherein the routing lines extendaxially and radially with respect to the distributor axis, away from thefluid line intersection, and wherein the routing lines are evenlycircumferentially distributed about the distributor axis at the fluidline intersection.
 6. The distributor of claim 2, wherein each routingline extends from the fluid line intersection to a line inlet into oneof the plurality of heat exchanger lines, and wherein the line inletsare arranged in a line parallel to the distributor axis.
 7. Thedistributor of claim 1, wherein the swirl vane is a helical orpropeller-shaped vane.
 8. The distributor of claim 1, wherein the swirlvane is an integral part of the distributor housing.
 9. The distributorof claim 1, wherein the swirl vane is a separate component installedwithin the distributor housing.
 10. A heat exchanger system comprises: aheat exchanger with a plurality of parallel heat exchanger lines,arranged along a common heat exchanger plane, each heat exchanger linehaving a line inlet; a distributor housing defining a main distributorline oriented along a distributor axis, and configured to receive anon-homogenous flow of the two-phase coolant fluid; a swirl vanedisposed within the main distributor line and configured to distributethe non-homogeneous flow into a rotationally symmetric fluiddistribution about the distributor axis; an atomizing nozzle disposeddownstream of the swirl vane; a plurality of routing lines, each leadingto one of the line inlets; and a rotationally symmetric fluid lineintersection situated downstream of the nozzle, and where the maindistributor line branches into the plurality of routing lines.
 11. Thedistributor of claim 10, wherein the swirl vane is a helical orpropeller-shaped vane.
 12. The distributor of claim 10, wherein the lineinlets are arranged in a line formed by the intersection of the heatexchanger plane with the heat exchanger housing.
 13. The distributor ofclaim 10, wherein at least one of the distributor housing and the swirlvane is formed of aluminum.